Around this time, many senators began to fear Caesar's growing power following his appointment as dictator for life. Brutus was persuaded into joining the conspiracy against Caesar by the other senators. Eventually, Brutus decided to move against Caesar after Caesar's king-like behavior prompted him to take action. His wife was the only woman privy to the plot.
The conspirators planned to carry out their plot on the Ides of March (March 15) that same year. On that day, Caesar was delayed going to the Senate because his wife, Calpurnia Pisonis, tried to convince him not to go. The conspirators feared the plot had been found out. Brutus persisted, however, waiting for Caesar at the Senate, and allegedly still chose to remain even when a messenger brought him news that would otherwise have caused him to leave.
When Caesar finally did come to the Senate, they attacked him. Publius Servilius Casca Longus was allegedly the first to attack Caesar with a blow to the shoulder, which Caesar blocked. However, upon seeing Brutus was with the conspirators, he covered his face with his toga and resigned himself to his fate.The conspirators attacked in such numbers that they even wounded one another. Brutus is said to have been wounded in the hand and in the legs.
Marcus Junius Brutus.
After the assassination, the Senate passed an amnesty on the assassins. This amnesty was proposed by Caesar's friend and co-consul Marcus Antonius. Nonetheless, uproar among the population caused Brutus and the conspirators to leave Rome. Brutus settled in Crete from 44 to 42 BC.
In 43 BC, after Octavian received his consulship from the Roman Senate, one of his first actions was to have the people that had assassinated Julius Caesar declared murderers and enemies of the state. Marcus Tullius Cicero, angry at Octavian, wrote a letter to Brutus explaining that the forces of Octavian and Marcus Antonius were divided. Antonius had laid siege to the province of Gaul, where he wanted a governorship. In response to this siege, Octavian rallied his troops and fought a series of battles in which Antonius was defeated